wscons key assigments for USB keyboard

Hello,
I went to do a simple wscons key reassignment - setting the left Windows
key to Control_L - and got the following error:
# sudo wsconsctl -w map+="keysym Meta_L = Control_L"
wsconsctl: Meta_L: not found
Running 'wsconsctl -k map' does not list either Meta_L nor Control_L for
this USB keyboard. My old AT system uses a PS/2 leyboard and the key
assignment works fine. Is it possible to do what I want with a USB
keyboard?
-Jeff W